Support base



FIG. 1 is a perspective view of a support base showing a new design;

FIG. 2 is a left side elevation view thereof, the right side being a mirror image;

FIG. 3 is a front elevation view thereof, the rear being a mirror image;

FIG. 4 is a top plan view thereof;

FIG. 5 is a bottom plan view thereof;

FIG. 6 is another perspective view of the support base of FIG. 1, but shown with broken line subject matter;

FIG. 7 is a left side elevation view thereof, the right side being a mirror image;

FIG. 8 is a front elevation view thereof, the rear being a mirror image;

FIG. 9 is a top plan view thereof;

FIG. 10 is a bottom plan view thereof;

FIG. 11 is yet another perspective view of the support base of FIG. 1, but shown with the broken line subject matter appearing as transparent;

FIG. 12 is a left side elevation view thereof, the right side being a mirror image;

FIG. 13 is a front elevation view thereof, the rear being a mirror image;

FIG. 14 is a top plan view thereof; and,

FIG. 15 is a bottom plan view thereof.

The dashed lines are included for the purpose of illustrating portions of the support base and environmental subject matter that form no part of the claimed design. 

CLAIM The ornamental design for a support base, as shown and described. 